I was wondering how much or if cold weater affects nute uptake in plants? I know what can happen with high heat and other than plants freezing in real cold weather I dont really have a clue about this and had to ask.
Phosphorus is greatly affected by the cold. Anything below 60°f-ish will start to show phosphorus deficiency and purpling will set in. Cold has a very measurable effect on the microbial activities in your media. They are responsible of "all" the uptake when dealing with "organic" fertilizers.